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In many young orogens of the Mediterranean region, Quaternary tectonics and regional uplift are traditionally considered strictly correlated, but few data are actually available for precise calculations of uplift rates. Such quantitative studies are needed to define the relationships between local faulting and large-scale uplift, and to formulate correct hypotheses on the geodynamic scenario in which the regional raising occurred. In addition, data about burial depths of sediments or tectonic loadings suffered by sedimentary and low-grade metamorphic rocks are essential for comparisons with the uplift rates obtained in the same areas. Such comparisons between quite different data sources improve the comprehension and choice of the most reliable mechanism responsible for the regional uplift and exhumation. Uplift rates have been calculated for a large sector of the Lucanian Apennine (axial zone of the southern Italian Apennines), and also reviewed for the Calabrian arc (southern termination of the Italian peninsula), using both geomorphological observations (elevation values, ages, and arrangement of depositional and erosional land surfaces and other morphotectonic indicators) and stratigraphical and structural data (sea-level related facies, base levels, fault kinematics, and offset estimations). Such data have been compared with those derived from clay mineralogy of Mesozoic pelagic deposits (Lagonegro units), outcropping in the same sector of the chain, which give information on burial depths. The values of the Quaternary uplift rates of the southern Apennines axial zone vary from a minimum of 0.2 mm/yr near the town of Potenza to a maximum of ~1.2-1.3 mm/yr in Agri high valley, a severely deformed Quaternary intermontane basin, still tectonically active, in the Pollino Mountains, a carbonate ridge with elevation up to 2200 m above sea level (asl); intermediate values (0.5–0.7 mm/yr) have been calculated for the other studied areas. The erosion rate from a key area of the Lucanian Apennine, obtained from both quantitative geomorphic analysis and missing volumes calculations on a catchment basin as wide as 150 km2, has been estimated at 0.2 mm/yr for the middle Pleistocene to Holocene time span. Since in the upper part of that chronological interval erosion and uplift rates match well, the axial-zone landscape could have reached a fl ux steady-state during the late Pleistocene. Using geomorphological features and late Pliocene to Pleistocene deposits involved in the genesis of erosional and depositional land surfaces, similar rates (≈0.6 mm/yr) have been obtained for a quite large time span (~2 m.y.) in the Melandro basin and adjacent Maddalena Mountains. Therefore, during the last 2 m.y., the total uplift amount of the axial zone of the Lucanian Apennine is ~1.2–1.3 km, with local peaks of 1.5 km. On the other hand, the Mesozoic pelagic units experienced tectonic loading\ud of 4–5 km, as estimated by means of illite crystallinity (in the range 0.6–1.1 Δ°2θ), percentage of illitic layers in illite/smectite mixed...

Uplift and erosion rates have been calculated for a large sector of the Campania-Lucania Apennine and Calabrian arc, Italy, using both geomorphological observations (elevations, ages and arrangement of depositional and erosional land surfaces and other morphotectonic markers) and stratigraphical and structural data (sea-level related facies, base levels, fault kinematics, and fault offset estimations). The values of the Quaternary uplift rates of the southern Apennines vary from 0.2 mm/yr to about 1.2-1.3 mm/yr. The erosion rates from key-areas of the southern Apennines, obtained from both quantitative geomorphic analysis and missing volumes calculations, has been estimated at 0.2 mm/yr since the Middle Pleistocene. Since the Late Pleistocene erosion and uplift rates match well, the axial-zone landscape could have reached a flux steady state during that time, although it is more probable that the entire study area may be a transient landscape. Tectonic denudation phenomena -leading to the exhumation of the Mesozoic core of the chain -followed by an impressive regional planation started in the Late Pliocene have to be taken into account for a coherent explanation of the morphological evolution of southern Italy.

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Abstract:The Agri River high valley is a Quaternary intermontane basin located in southern Italy. The tectonic evolution of this basin was controlled by Lower Pleistocene strike-slip master faults, subsequently reactivated as normal faults until the Middle Pleistocene. The Quaternary sediments of the basin infill are mainly constituted of continental clastics, represented by coarse-grained alluvial deposits divided by unconformities. The arrangement of clastic deposits suggests that the Pleistocene to Holocene alluvial fan system developed along the eastern margin of the valley. Five generations of slope and alluvial fan systems have been recognized in the Agri basin. The oldest fans have formed on both slope and alluvial deposits. The younger alluvial fans are located along the entire valley floor and arose upon the earlier fan apexes originating in these valleys. The youngest fans are arranged in two different generations and show proximal facies distributed along the foot slopes. Plan view morphology, fan slope profiles, and sedimentary features of the fan system have been used here to determine the magnitude of the tectonic deformation episode affecting the faulted mountainous front of the Agri basin eastern margin. Both fast and slow tectonic episodes occurred during the different regional Quaternary tectonic stages that affected the southern Apennine chain. These tectonic episodes have therefore been analysed in relation to climatic conditions in order to determine their contributions to the evolution of the Pleistocene to Holocene fan systems.

Morphometric analyses of both the topography and drainage network have been carried out in a large sector of the Ionian coastal belt of southern Italy in order to unravel the possible control of Late Quaternary thrust front activity on the evolution of the fluvial net. The study area extends in the southernmost sector of the Bradano Foredeep and is featured by several orders of uplifted marine terraces, ranging in age from Middle Pleistocene to Late Quaternary. The flight of the marine terraces is deeply cut by a trellis-type and regularly spaced minor fluvial network. Morphotectonic investigations based on field survey, photo-aerial interpretation, topographic attributes, morphometric indices, and analysis of longitudinal river profiles suggest a strong control on the drainage network arrangement by a pervasive orthogonal fracture system, produced and preserved into the brittle caprock of the terraces, made by conglomerate. Since a similar pervasive and orthogonal fracture pattern is typically generated by gentle folding of rocks, the development of the Ionian hydrographic networks could be attributed to a general—maybe still active—bending of the foredeep area due to the eastward propagation of blind thrusting of the Apennines orogenic chain.